Hydroxysafflor yellow A reduces myocardial infarction size after coronary artery ligation in rats.

This study was undertaken to determine the cardioprotective effect of hydroxysafflor yellow A (HSYA), at doses of 2, 4 or 8 mg/kg, extracted from the flower of the safflower plant, Carthamus tinctorius L. (Asteraceae), on acute myocardial ischemia induced by left anterior descending coronary artery (LAD) ligation in rats. The myocardial infarction size (MIS), creatine kinase (CK-MB) activity, endothelial nitric oxide synthase (eNOS) activity, superoxide dismutase (SOD) activity, malondialdehyde (MDA) content and nitric oxide (NO) content were measured. The results showed that administration with hydroxysafflor yellow A at doses of 4 or 8 mg/kg resulted in a reduction in myocardial infarction size. Hydroxysafflor yellow A (4 or 8 mg/kg) inhibited not only the elevation of creatine kinase activity and malondialdehyde content but also the reduction of superoxide dismutase activity, endothelial nitric oxide synthase activity and nitric oxide content. The findings suggested that hydroxysafflor yellow A (4 or 8 mg/kg) exerted cardioprotective effects against acute myocardial ischemic injury by regulating superoxide dismutase activity and endothelial nitric oxide synthase activity. [ABSTRACT FROM AUTHOR]